Undine Valentine is a minor, somewhat mysterious character from the Guilty Gear series, typically associated with Valentine, a major antagonist. Undine serves as an alter-ego or alternate form for Valentine, often appearing during special events or in supplementary materials. Her appearance and actions are closely tied to the main narrative involving the Valentines and their mission. While not a main character, Undine's presence adds depth to the lore and the enigmatic nature of the Valentine's role in the conflict.